CN111033944A

CN111033944A - Pre-assembly seat and method for forming a crown from a plurality of U-shaped conductive hairpins for the subsequent mounting of the crown in a mechanical element of an electrical machine

Info

Publication number: CN111033944A
Application number: CN201880053395.8A
Authority: CN
Inventors: M·梅茨格; M·施默尔茨
Original assignee: Grob Werke GmbH and Co KG
Current assignee: Grob Werke GmbH and Co KG
Priority date: 2017-06-20
Filing date: 2018-06-20
Publication date: 2020-04-17
Anticipated expiration: 2038-06-20
Also published as: US20200177065A1; CN111164857B; WO2018233774A1; DE102018114875A1; CN111033944B; US20220069682A1; CN111164857A; EP3642934A1; US20200212771A1; DE102018114846A1; EP3642933B1; WO2018233769A1; US11218061B2; WO2018233771A1; US11652392B2; EP3642933A1; DE102018114780A1; US11522423B2

Abstract

The present invention relates to a pre-assembly seat 100 and a method for forming a crown from a plurality of U-shaped conductive hairpins, so as to be able to subsequently install the crown in a mechanical element of an electric machine, such as a stator. Here, the receiving member (10) has a plurality of slots (11) in which legs of the hair clip are received. The channel (11) is arranged annularly around the center Z and extends perpendicular to the plane of the receiving member (10). They are configured in such a size and geometry that the first leg of the hair clip rotates in each case within the channel (11), so that the second leg of the hair clip can be positioned in the other channel (11) without restraint. One or more crowns formed by the hair clip are introduced into and assembled into the mechanical element.

Description

Pre-assembly seat and method for forming a crown from a plurality of U-shaped conductive hairpins for the subsequent mounting of the crown in a mechanical element of an electrical machine

Technical Field

The present invention relates to a pre-assembly seat and a method for forming a crown from a plurality of U-shaped conductive hairpins, in order to be able to subsequently mount the crown in a mechanical element of an electrical machine. The invention also relates to a device for producing a mechanical component of an electrical machine.

Background

An electric machine is generally understood to mean, in particular, a machine which converts electrical energy into kinetic energy, and a machine which converts kinetic energy into electrical energy. In particular, the term is to be understood as electric motors and generators.

When manufacturing the mechanical elements of such machines, such as the stator and the rotor, it is often necessary to connect the ends of the electrical conductors formed by the wires to each other or to machine them together in another way, such as cutting or shaping.

For example, there is an electric motor, in particular, in which a coil winding of a stator is formed of a plurality of wires whose ends are connected together. These wires are commonly referred to as hairpins. In particular, the metal wire forming the hair clip may have a rectangular cross-section, may be configured as a flat, rectangular or profiled steel wire, or may be a flat strip steel or the like.

For example, a stator member having a plurality of slots is used to accommodate the hair pin.

An example of a known card is shown in a side view in figure 2 a. The hair clip 1 has two

legs

1a,1b extending parallel to each other, several angles of extension forming a roof shape, also called house roof shape. In order to assemble a plurality of hair clips in the most dense manner possible when manufacturing the stator, it is common to bend the hair clip top area in a direction extending perpendicular to the hair clip plane (i.e. perpendicular to the plane of the drawing of fig. 2 a).

Fig. 2b shows an enlarged view looking down onto the hairpin roof from above. In the illustration, the two

legs

1a,1b of the hairpin 1 extend perpendicular to the plane of the drawing. The wire bent in this way has a three-dimensional or 3D shape.

In order to manufacture a stator using, for example, hair clips as electrical conductors, it is often necessary to mount different hair clips in the stator to form one or more annular crowns. The individual hair clips are electrically connected to each other at their ends or at the ends of their legs, thereby forming a densely packed coil winding in a single or multiple crowns. The ends of the hair clip are typically joined by welding.

In order to connect each phase of the stator to the power electronics system, elements, for example for corresponding interconnections, are electrically connected to the crown assembly.

In the hitherto known methods of manufacturing stators using the hairpin technique, the hairpin is manually mounted directly into the stator.

Fig. 3a shows an overhead view of a known stator 200, which stator 200 has a plurality of slots 211 for receiving the hair clip 1. The

legs

1a,1b of the hair card 1 are positioned by being fitted into the slot 211.

Fig. 3b shows an enlarged aerial view of a part of the known stator. The two

legs

1a,1b of a single hairpin or a single hair pin fit into designated

slots

211a,211b, respectively. The two slots are spaced apart so that the hair clip or pin extends across the plurality of slots 211 between them along the roof to where the other hair clips are fitted, thereby forming a crown arrangement of overlapping hair clips. In order to obtain a high packing density of the hair pins and thus a high packing density of the stator windings, it is necessary to arrange the hair pins very compactly.

The technique of producing mechanical elements, such as stators, has the following drawbacks, for example when using hairpins, in particular:

manually installing the hairpin into the stator is time consuming and costly.

The slots 211 are arranged radially as viewed from the center of the stator so that there is little clearance for the U-shaped hair pins or hair pins in the respective slots. However, for the assembly process, after all of the hair pins have been mounted to the stator in their final position, the outer legs of the hair pins must be mounted on a radius that is further than the radius behind in the stator. This cannot be reliably achieved in the case where the slots in the stator are arranged in a radial pattern.

Therefore, after the hairpin is installed in the stator, tension may be generated in the hairpin, which may have an adverse effect.

In addition, existing arrangements can create tension that pulls the assembled needle or assembled hairpin toward the center of the containment device. This is disadvantageous for the subsequent working process.

Disclosure of Invention

The aim of the invention is, for example, to be able to automatically assemble hairpins and to ensure that the assembly process is reliable with a high packing density when manufacturing mechanical components such as stators.

In order to achieve this object, the invention provides a pre-assembly seat for forming a crown from a plurality of U-shaped conductive hairpins, so as to be able to mount the crown in a mechanical element of an electric machine, comprising: a receiving member with a plurality of slots for receiving the legs of a U-shaped hair clip, wherein the slots are arranged annularly around a center Z and extend perpendicularly to the plane of the receiving member, as a result of the slot being configured to such a size and geometry that the first leg of the hair clip can be rotated in each case within the slot, so that the second leg of the hair clip can be positioned without limitation in another slot.

Previously, by pre-assembling the base to form one or more crowns of the U-shaped hair clip, reliable, high packing density automated assembly, for example, by a robot, may be achieved, for example, prior to installing the hair clip in the stator. The invention also allows the hair pins to be collected or assembled in a holding device to form a crown. For example, the different crowns can be collected in a containing device so that they can be inserted later into the mechanical element, in particular the stator.

Advantageously, the slot of the receiving member is much larger than the cavity for receiving the mechanical element of the hairpin or the cavity of the stator. This allows for a better automated assembly of the u-shaped clip or hair clip.

The slot of the receiving member is configured in a manner that the hair clip moves to a desired position in the receiving member under the influence of gravity. Thus, better when the hairpins are in their intended positions, this will make the positioning process easier.

Preferably, the channels of the containing member are arranged radially around the centre Z. In particular, they may have a side wall extending in a radial direction, centred on Z. For example, the slot may have a width B that increases radially outward.

Advantageously, the channels of the containing member are arranged offset or slightly offset with respect to each other, for example in the shape of a turbine. Thus, one leg of the card is more easily rotated about the center of the other leg in the receiving member. Therefore, the hair clip can be better protected from damage when the hair clip is installed. They have a greater clearance in the receiving members and are not subjected to any forces.

The channel body accommodating the members has in each case a side wall extending in the direction of the point P outside the center Z. Specifically, the point P of each tank may be arranged on a circle centered on the center Z.

These actions further improve the unconstrained positioning of the hair clip and further reduce the risk of possible damage.

Preferably, the receiving member has an inner ring, and a side wall of the groove is formed on an outer surface of the inner ring to hold the hairpins in respective positions.

Preferably, the receiving member has an outer ring, and a side wall of the groove is formed on an inner surface of the outer ring to hold the hairpins at respective positions.

In particular, the receiving member may be configured without an inner ring or without an outer ring. In this case, the hairpins are held in their position by the geometry of the receiving members.

In particular, the receiving member may have an inner ring and an outer ring with a hollow chamber formed therebetween as a slot.

For example, the receiving member has a retaining member provided on the inner ring and/or the outer ring so as to form a groove. In particular, the receiving member may have a holding member configured as a bolt, a stud, a metal sheet, or the like, so as to receive the hairpin or form a slot for receiving the hairpin.

Advantageously, the slot is configured in such a way as to enable the formation of a plurality of annular crowns of each hairpin by means of the legs housing the same. For example, after forming the crown, the individual crowns may be joined together, for example, in a containment member configured as a collection container.

For example, the slot may have an incline and/or one or more offsets to position one or more hairpins or hairpin crowns in a radial direction. The radial positioning of the individual crowns ensures that the multiple crowns are joined in the receiving member. Further, the crown to be joined can be prevented from colliding with the joined crown.

Due to the presence of the ramps and/or offsets, for example formed on the upper side of the receiving member in the region of the slot, the hair clip or the hair clip crown is brought to the outer diameter and positioned there by gravity or external forces.

Advantageously, the pre-assembly seat has a frustoconical shape in the region of the groove.

In particular, the trough body may have side walls, the upper ends of which are formed with an incline and/or one or more steps.

For example, the pre-assembly seat is configured as a multiple pre-assembly seat for forming multiple crowns.

In particular, due to the geometry of the housing members, the invention enables the robot to assemble the hair clips together to form the crowns in an automated manner, and also to collect a plurality of crowns in the housing device.

According to one aspect, the invention provides a device for manufacturing a mechanical element of an electric machine, comprising a pre-assembly seat for forming crowns from a plurality of U-shaped conductive hairpins, a mechanical element housing for housing the hairpins, and means for conveying and inserting the U-shaped hairpin crowns into the mechanical element housing.

In particular, in this case, the pre-assembly seat can be configured according to the invention.

According to another aspect, the invention provides a method of forming a crown from a plurality of U-shaped conductive hairpins so as to be subsequently able to be mounted into a mechanical element of an electrical machine, the method comprising the steps of:

-providing a plurality of U-shaped conductive hairpins;

-connecting the hair clip by fitting its legs into the receiving member, so that the plurality of hair clips together form a crown;

wherein, when the respective hair clip is fitted into the receiving member, a first leg of the hair clip is rotatably held in the receiving member so that a second leg of the hair clip can be positioned in the receiving member by rotation about the first leg;

-then providing a crown consisting of hair clips to introduce them into the hair clip receiving means of the mechanical element.

Advantageously, the receiving member has a slot for receiving the hair clip, which is larger than the slot for receiving the mechanical element of the hair clip or the slot of the stator.

For example, the channels may be arranged in a radial pattern. They may also be arranged offset with respect to each other.

Preferably, the hairpins fall into their respective intended positions due to the influence of gravity.

Advantageously, the plurality of crowns are formed and then joined to form the multi-layered crown member.

Preferably, the one or more crowns are inserted into the mechanical element or stator after the one or more crowns are manufactured. The multiple crowns may be inserted into the mechanical element or stator individually, one after the other, and as an assembly.

In particular, the method is carried out using a pre-assembly seat according to the invention.

According to another aspect of the invention, a pre-assembly socket according to the invention is used for carrying out the method according to the invention.

According to another aspect, the device according to the invention is used to perform the method according to the invention.

The advantages and details of the invention relating to the pre-assembly seat according to the invention also apply to the device according to the invention and to the method according to the invention, just as the advantages and details of the invention relating to the method according to the invention or to the device according to the invention also apply to the pre-assembly seat according to the invention.

Drawings

Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings. In the figure:

fig. 1 shows an aerial view of a pre-assembled seat according to a preferred embodiment of the invention.

Fig. 2a and 2b show a schematic side view of a known hair clip (fig. 2a) and a view looking down from above (fig. 2 b).

Figures 3a and 3b show a top view (figure 3a) and a partially enlarged view (figure 3b) of a known stator having a plurality of slots for receiving a hairpin as a whole and as an overhead view.

Fig. 4a and 4b show a top view of a pre-assembly nest with offset mesh of the invention (fig. 4a) and a partial enlarged view thereof when viewed overhead (fig. 4 a).

Figure 5 is an enlarged schematic view of a pre-assembly cartridge with an offset mesh or offset channel of the present invention.

Fig. 6a and 6b show a front view (fig. 6a) and an overhead view (fig. 6b) of a pre-assembled seat with an inclined portion formed on its upper part.

Fig. 7a and 7b show a front view (fig. 7a) and an overhead view of a pre-assembled seat with a step formed on its upper part.

Fig. 8 shows an overhead view of the pre-assembled seat of the invention without the outer ring.

Fig. 9 shows an overhead view of the pre-assembled seat of the invention without the inner ring.

Detailed Description

Fig. 1 shows a pre-assembly seat 100 according to a preferred embodiment of the invention in a top view. The pre-assembly mount 100 is used to form at least one crown from a plurality of U-shaped conductive hairpins, so that the crown can be subsequently installed in the mechanical element of the electrical machine. In this example, the crown is to be mounted in a stator, in particular suitable for an electric motor of a motor vehicle.

The pre-assembly holder 100 comprises a receiving member 10, which receiving member 10 has a plurality of slots 11 for receiving the

legs

1a,1b of the U-shaped hair card 1. An example of the known hair clip 1 is described above, with reference to fig. 2a and 2 b. However, a different card issuing structure than that shown in fig. 2a and 2b may also be accommodated in the device 100.

In the containing member 10, the grooves 11 are arranged annularly around the center Z of the pre-assembly seat 100. Here, the channel 11 extends perpendicular to the plane of the receiving member 10, i.e. perpendicular to the plane of the drawing of fig. 1.

The slot 11 is constructed such that the first leg 1a of a hair clip 1 can be rotated in each case within the slot 11 in terms of the size and geometry of the slot, so that the placement of the second leg 1b of a hair clip 1 within another slot 11 can be unrestricted. (see also fig. 2a, 2 b).

The channels 11 of the receiving member 10 are arranged radially around its centre Z. The channel has

side walls

11a,11b extending in radial direction with respect to the centre Z. The width B of the channel 11 increases outwardly in the radial direction.

The slot 11 of the receiving member 10 is constructed to be much larger than the cavity or slot that will later receive the stator of the card 1. This facilitates the assembly of the clevis and the assembly can be carried out in an automated manner.

Due to the geometry of the arrangement of the slots, when the corresponding hairpin 1 is inserted into the slot 11 of the receiving member 10, the hairpin 1 can be rotated about its leg 1a already received in the slot 11. This means that the leg 1a in the channel 11 will be the axis of rotation. The crowns of the hairpins 1, which are stacked on top of each other (which are inserted into the stator later, i.e. after removal from the pre-assembled seat 100), are formed in an unconstrained manner in the pre-assembled seat 100.

In contrast, in the known stator shown in fig. 3, when the hairpin is inserted, each hairpin leg 1b cannot rotate about the rotation point R. This means that, here, the single hairpin 1 cannot rotate around the leg 1a already mounted in the slot 211a of the stator 200, and therefore, the rotation R' does not occur. Therefore, the tension generated during or after assembling the hairpin to the stator may be adversely affected.

Due to the enlargement of the slots 11 of the pre-assembly seat 100 according to the invention compared to the stator and the geometry and arrangement of the slots 11, the

legs

1a,1b of the hair clip can be rotated in the respective slots 11 during the assembly process, and the hair clip 1 can be positioned in the pre-assembly seat 100 in an automated manner, for example by a robot. Tension is avoided when the hairpin 1 is assembled.

The hairpin can then be inserted in an automated manner into a future stator in the form of a finished crown or a crown assembly with several crowns. The invention also relates to a stator for a motor vehicle, comprising a stator housing, a stator ring, a stator.

Fig. 4a and 4b show a further embodiment of the invention in top view or in an overhead, partially enlarged view. Figure 5 shows an enlarged view of the aerial view. In the pre-assembly seat 100 according to this example, the groove 11 is arranged in a slightly offset manner. This arrangement may be referred to as a turbine shape.

The

side walls

11a,11b of the housing 11 extend beyond the centre Z of the pre-assembly seat 100 in the direction of the point P (see figure 5). The point P of each tank 11 is arranged on a circle around the center Z.

In the exemplary embodiment, the width B of the channel 11 also increases radially outward. Further details and features of this exemplary embodiment are as described above and please refer to the first exemplary embodiment.

When positioning the hair clip 1, the hair clip 1 can rotate about its leg 1a in the slot 11. The rotation point or axis is marked R in fig. 4 b. As a result, the other end of the hairpin, i.e. its leg 1b, can rotate about the rotation point or axis R of rotation in the receiving member 10 or its slot 11. The rotational movement of the leg 1b about the leg 1a is marked R'.

The geometry of the channel 11 is configured to enable the above-mentioned rotation. Since the hair card has more space in the receiving means and is not subjected to any forces, the hair card is not damaged during installation. Furthermore, the hair clip will fall into the desired position better and more easily due to the influence of gravity.

The offset slots or offset webs may provide more clearance for the card. This further improves the tension-free arrangement of single or multi-crown hair clips.

Fig. 6a and 6b show another possible embodiment of the invention. Here, the upper portion of the pre-assembly holder 100 is formed with an inclined portion 18 extending in a radial direction. In this example, the inclined portion 18 is configured to taper radially outward. Each of the ramps 18 is located at the upper end of the channel 11, respectively, and functions to bring the hair pin, hair clip or crown formed therefrom to the outer diameter or radius of the receiving member 10 and to be positioned there by the influence of gravity and/or external forces.

Fig. 7a and 7b show different possible embodiments of the invention, in which the upper side of the pre-assembly seat 100 is radially formed with a step or offset 19. In this example, the steps 19 are located at the upper edge of the tank 11 and are configured to taper radially outwardly. As with the ramp 18 described above, the step or offset 19 enables the hair pin, hair clip or crown formed therefrom to reach the outer diameter or radius of the receiving member 10 and be correspondingly positioned there under the influence of gravity and/or external forces.

This means that when a single hair pin or a crown formed by a hair pin is fitted into the slot 11 from above, the hair pin or hair pin crown is moved outwards to a desired radial position by the ramps 18 and/or the steps 19.

The incline 18 and the step 19 may also be combined with each other.

In particular, as described above with reference to fig. 6a and 6b or fig. 7a and 7b, the radial positioning of the hair clip by the sloping 18 and/or the step 19 of the slot 11 has the effect that once the crown of the hair clip 1 is formed, a plurality of crowns can be connected and positioned.

The respective crowns formed by the hair clip can be positioned in the receiving device or receiving member 10 in a defined manner in the radial direction and held there, so that the crown to be joined does not collide with the already joined crowns.

Hereby it is ensured that the engagement of the plurality of crowns in the receiving means or receiving member 10 is reliable. In this case, the containing member 10 forms a collecting container for connecting a plurality of crowns.

Fig. 8 also shows another possible configuration of the receiving member 10. In the figures, the receiving member 10 has an inner ring 14 but no outer ring. Instead, the hair pins or hairs are held in the desired position by the geometry of the receiving member 10. To achieve this, a groove 11 is formed on the outer surface of the inner ring 14 of the receiving member 10. The

side walls

11a,11b of the housing 11 extend radially outwardly from the outer surface of the inner ring 14.

To this end, a finned web or projection 16 extends outwardly or radially outwardly from the outer surface of inner ring 14 on inner ring 14. Thus, the protrusions 16 form holding members of the hair clip 1. For example, bolts, spikes, metal tabs or other retaining members may also be mounted on the inner ring 14 that receive the hair pins or form a channel for receiving the hair pins.

Fig. 9 shows another possible configuration of the containing member 10, in which only the outer ring 15, and not the inner ring, is present. A finned web or projection 16 extends inwardly or radially inwardly from the outer ring 15 to form a retaining member for the hair clip 1. In this case, for example, bolts, spikes, metal plates or other retaining members may also be mounted for receiving the hair pins or to form a channel capable of receiving the hair pins.

It is also possible to provide both an inner ring 14 and an outer ring 15, between which the slots for receiving the

hairpin legs

1a,1b extend.

A method of forming the crown portion from a plurality of U-shaped conductive hairpins will be exemplified below. The method is used for the subsequent mounting of a crown in a mechanical element of an electrical machine, in particular in the stator of an electric motor for a motor vehicle.

In this method, a plurality of U-shaped conductive hairpins 1 are first provided (see fig. 2a and 2 b).

Now, the plurality of hair clips 1 are engaged by fitting the

legs

1a,1b of the hair clip 1 into the receiving member 10 (see, for example, fig. 1 and 5). The plurality of hairpins 1 form a crown portion together in this manner.

When the hair pins 1 are fitted into the receiving member 10, the first legs 1a of the respective hair pins 1 are rotatably held in the receiving member 10, so that the second legs 1b of the respective hair pins 1 can be positioned in the receiving member 10 by rotating around the first legs 1a (see, for example, fig. 4 b).

For easier and unconstrained positioning, the slot 11 in the receiving member 10 is much larger than the slot of the stator that later receives the hairpin. The channels 11 may also be arranged in a radial shape and/or offset with respect to each other.

During assembly, the hair pins 1 fall into their respective intended positions due to the influence of gravity.

In particular, as described above with reference to fig. 6a and 6b or fig. 7a and 7b, the inclined portion 18 or the offset portion 19 is provided for improved positioning.

The hairpin crown formed in this way is then subsequently introduced into a mechanical element or a hairpin receiver of a mechanical element, wherein the mechanical element is a stator in this example. The crown may then be inserted into the stator. Further, for example, a plurality of crowns may be inserted into the stator one by one.

In particular, if a pre-assembly nest 100 is used, multiple crowns may also be formed by joining individual hair clips in this method, and multiple hair clips may be joined to form a multi-layered crown member. These multi-crown components can then be removed from the pre-assembly nest 100 and inserted into the stator as a complete component.

In addition, several pre-assembled sockets may be used to manufacture a crown assembly consisting of several hairpin crown portions. In this case, hairpin crowns of different diameters are formed in one or several pre-assembled seats. The crowns of different diameters formed in this way are then arranged together in another pre-assembly seat, configured to achieve the aim of acting as a collecting container or collecting pre-assembly seat.

The formation of one or more crowns from the hairpin and the subsequent transport and insertion of the crowns into the housing of the mechanical element, for example the stator housing, is preferably carried out, for example, in an automated manner, such as by a robot.

Because of the geometry of the receiving device or receiving member 10, it is possible to crown the hair clip with a robot and collect a plurality of hair clip crowns in the receiving device.

Reference numerals

1 hairpin

1a,1b hairpin leg

10 receiving member

11 trough body

11a,11b side walls of the tank

14 inner ring

15 outer ring

16 raised, finned

18 inclined part

19 offset part

100 pre-assembly seat

200 stator

211 groove body of stator

211a,211b stator tank

Width of B groove body

Points other than P center

R rotation point or axis

R' rotary motion

Z center

Claims

1. A pre-assembly seat for forming a crown from a plurality of U-shaped conductive hair cards (1) so as to be able to subsequently install said crown in a mechanical element of an electric machine, said pre-assembly seat comprising:

an accommodating member (10) having a plurality of slots (11), said slots (11) being intended to accommodate the legs (1a, 1b) of the U-shaped hair clip (1), wherein,

the groove (11) is located on a circumference around the center Z and extends perpendicular to the plane of the receiving member (10), and

the slots (11) are configured to have such dimensions and geometries that the first leg (1a) of the hair clip (1) can rotate within the slot (11) in either case, thereby enabling the second leg (1b) of the hair clip (1) to be positioned unconstrained in another of the slots (11).

2. A pre-assembly seat according to claim 1, characterised in that the slot (11) of the housing member (10) is significantly larger than the cavity for housing the mechanical elements of the card (1).

3. A pre-assembled seat according to claim 1 or 2, characterised in that the slot (11) is configured such that the card (1) is moved to a desired position in the receiving member (10) by the influence of gravity.

4. A pre-assembled seat according to any one of the preceding claims, characterised in that the housing (11)

4.1 arranged radially around the center Z, and/or

4.2 have side walls (11a, 11b) extending in a radial direction with respect to the centre Z, and/or

4.3 has a width B which increases outwards in the radial direction.

5. A pre-assembled seat according to any one of claims 1 to 3, characterised in that the housing (11)

5.1. Are arranged offset with respect to one another, and/or

5.2. In each case having side walls (11a, 11b) extending in the direction of a point P outside the centre Z,

5.3. in each case with side walls (11a, 11b) extending in the direction of a point P outside the centre Z, wherein the points P of the individual channels (11) are arranged on a circle centred on the point Z.

6. A pre-assembled seat according to any one of the preceding claims, characterised in that said containing member (10)

6.1. Having an inner ring (14) on the outer surface of which the side walls (11a, 11b) of the channel (11) are formed to hold the hair card (1) in its respective position, and/or

6.2. Having an outer ring (15) on the inner surface of which the side walls (11a, 11b) of the slot (11) are formed to hold the hair clip (1) in its respective position, and/or

6.3 having an inner ring (14) and an outer ring (15), between which inner ring (14) and outer ring (15) the groove (11) is formed as a hollow space, and/or

6.4. Having retaining members arranged on the inner ring (14) and/or the outer ring (15) to form a channel (11), and/or

6.5. Has a retaining member configured as a bolt, stud or sheet metal to form a channel (11).

7. The pre-assembly holder according to any of the preceding claims,

7.1. the channel (11) is constructed in such a way that a plurality of annular crowns are formed by the legs (1a, 1b) accommodating the hairpin (1), and/or

7.2. The channel (11) has an inclined portion (18) and/or one or more offset portions (19) to position one or more of the hairpin legs (1a, 1b) or one or more of the crowns in a radial direction, and/or

7.3. The pre-assembly seat is in the form of a truncated cone in the area of the groove (11), and/or

7.4. The trough (11) has a side wall, the upper end of which is formed with the ramp and/or one or more steps, and/or

7.5. The pre-assembly seat is configured as a multiple pre-assembly seat for forming a plurality of crowns.

8. An apparatus for manufacturing a mechanical element of an electrical machine, comprising:

a pre-assembly seat for forming a crown from a plurality of U-shaped conductive hair cards (1),

a mechanical element housing for accommodating the hairpin (1), and

a device for conveying and inserting a crown consisting of the U-shaped hair clip (1) into the housing of the mechanical element.

9. The device according to claim 8, wherein the pre-assembly seat is configured according to any one of claims 1 to 7.

10. A method for forming a crown from a plurality of U-shaped conductive hair clips (1) so as to be able to subsequently mount said crown in a mechanical element of an electrical machine, comprising the steps of:

-providing a plurality of U-shaped conductive haircards (1);

-connecting the hair clip (1) by fitting the legs (1a, 1b) of the hair clip (1) into a receiving member (10) such that the hair clip (1) together form a crown;

-wherein, when fitting each hair clip (1) into the receiving member (10), a first leg (1a) of the hair clip (1) is rotatably held in the receiving member (10) to position a second leg (1b) of the hair clip (1) in the receiving member (10) by rotation around the first leg (1 a);

-subsequently providing a crown (1) consisting of said hair clip for introducing it into a hair clip receiving means (110) of a mechanical element (100).

11. Method according to claim 10, characterized in that the receiving member (10) has a slot (11) for receiving the hairpin (1), the slot (11)

11.1 is larger than the slot (111) of the machine element (100) for accommodating the hairpin and/or

11.2 are arranged in a radial pattern, and/or

11.3 are arranged offset with respect to one another.

12. Method according to claim 10 or 11, characterized in that the cards (1) fall into their respective intended positions due to the effect of gravity.

13. The method of any one of claims 10 to 12, wherein a plurality of crowns are formed and joined to form a multi-layered crown member.

14. Method according to any one of claims 10 to 13, characterized in that it is carried out by means of a pre-assembly seat according to any one of claims 1 to 7.

15. Use of a pre-assembly seat according to any of claims 1 to 7 for carrying out a method according to any of claims 10 to 14.

16. Use of the apparatus according to claim 8 or 9 for performing the method according to any one of claims 10 to 14.